Innovations: Limit your exposure to CO

“If you think you may be suffering from CO exposure, lean the mixture aggressively, provided any change in performance can be tolerated,” he advises. “Rich mixtures result in high levels of CO in the exhaust, lean mixtures (EGT’s lean of peak) have practically none.”

He noted that engines with well-balanced fuel to air ratios — such as those equipped with a GAMIjector fuel injector — can almost always be operated lean of peak and continue to operate smoothly, but even carbureted engines that typically have relatively poorly balanced fuel to air ratios will tolerate lean operation at the expense of some engine roughness.

To help explain, he sent along the graph above, which is part of the company’s Advanced Pilot Seminars.